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Cisco Bug: CSCvu11993 - ZBFW drops selfzone generated packets from CPU to host with invalid reason in 16.12.x routers

Last Modified

Sep 10, 2020

Products (1)

  • Cisco XE SD-WAN Routers

Known Affected Releases

16.12.1

Description (partial)

Symptom:
With ZBFW enabled on 16.12.x routers a packet processing for some traffic with IP options which is punted to CPU ( TTL=1 or DF bit set for a large packet like Traceroute or PMTU Discovery) is not working as expected, return traffic from router CPU to host is dropped by Firewall feature for selfzone generated packets.

Conditions:
- ZBFW enabled on cedge 16.12.x
- Router receives an incoming packet with IP options ( TTL=1 or DF bit set for a large packet like Traceroute or PMTU Discovery)
- a Response packet from Router CPU to host is dropped with a code FirewallL4Insp (selfzone generated packets)
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Bug Details Include

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